Scientists are revising the history of one of the world’s most important crops. Drawing on genetic and archaeological evidence, researchers have found that a predecessor of today’s corn plants still bearing many features of its wild ancestor was likely brought to South America from Mexico more than 6,500 years ago. Farmers in Mexico and the southwestern Amazon continued to improve the crop over thousands of years until it was fully domesticated in each region.

Indigenous peoples in the Chesapeake harvested oysters sustainably for thousands of years—until the introduction of new techniques by Europeans decimated the stocks.

As long as 3,200 years ago, Indigenous peoples living along the banks of the Chesapeake Bay harvested oysters in vast quantities. They extracted the meat and piled the shells into mounds known as middens. Archaeologists have long studied these shell mounds—some of which are meters deep—for a window into the lifestyles of these peoples: what they ate, how they hunted, and the tools they used. Now, clues unearthed in these mounds also suggest they likely knew a thing or two about how to sustainably harvest oysters.

“Despite the significant role oysters played in the Native American diet back then, they weren’t overexploited,” says archaeologist Alex Jansen, leader of a recent study analyzing the middens.

“Even though it is possible that these early societies may not have been practicing sustainable harvesting intentionally, it appears they were able to balance management with fishery needs,” Jansen adds. “That’s something we need to get back to.”

Since the early 1900s, overfishing in the Chesapeake Bay has led to steep declines in oyster stocks. Around 1990, oyster harvests across the bay were less than one percent of historical levels. Harvesting techniques introduced by European colonists during the 18th and 19th centuries, such as dredging and tonging, were responsible for much of this enormous toll. These destructive techniques rip living oysters from the reef, often before they’re fully grown, reducing the size and damaging the structure of the reef.

Given that oysters play an important role in filtering algae, plankton, and other particles from the water, the depletion of the bay’s oysters caused the water quality to suffer. The destruction of wave-buffering oyster reefs also reduced the protection they offered to the shoreline.

Examining shell middens near Chesapeake Bay showed Jansen that the Indigenous peoples’ harvesting practices were much less destructive, which is what allowed them to exploit oysters for thousands of years.

Jansen also found tools such as ceramics, projectile points, and stones used for heating water at the study site. But based on his analysis, these tools were not used for oyster harvesting, which, he says, was mostly done by hand. He also noted the large sizes of the oyster shells, which suggests the oysters were given time to grow and reproduce before being snagged.

Throughout the thousands of years captured in the shell middens, “the oysters were largely consistent in shape and size,” Jansen says. He says the oysters were likely harvested from the water close to shore, rather than from deeper waters where reefs form. “By leaving the reefs alone and intact, Native American harvesters were able to give the oysters a chance to reproduce and restock the bay.”

Today, after years of restoration efforts, oyster populations in the Chesapeake Bay are showing signs of a rebound. Carmera Thomas, a program manager for the Chesapeake Bay Foundation, says that over the past few decades, millions of baby oysters attached to recycled oyster shells have been placed on sanctuary reefs throughout the bay, contributing to the restoration of oyster reefs on target tributaries. In 2017, a bill proposed by state officials and watermen in Maryland to open more than two million square kilometers of oyster sanctuary to harvest did not pass.

Despite the momentum, Thomas says pressure on wild oyster populations will continue unless we learn lessons from the past and put some ancient practices into play.

“If we as a population were more diligent about restoring what is taken out of the bay, using less invasive tools, and not harvesting as much … it would put less stress on the population,” Thomas says.

Jansen agrees. Even though we no longer have the same technological limitations as our ancestors, that doesn’t mean we can’t heed the lessons of the past and leverage simpler approaches. Only this time, the act of conservation would undoubtedly be intentional.

Sambaqui societies had sophisticated diet. Study suggests that hunter-gatherer communities living in coastal Atlantic Forest areas between 8,000 and 1,000 years ago consumed a range of plants and more carbohydrates than expected for the period and region.

We may think of potatoes as the most basic of foods, given their modern ubiquity and low cost, but in the Moche culture in ancient Peru, archaeologists had assumed they were highly charged symbols of the elite because they were found only in artifacts. New research, however, has shown that our understanding of New World potato consumption is biased by the fact the starchy vegetable is nearly always consumed in its entirety.

In a forthcoming article in the Journal of Archaeological Science, researchers Guy Duke of the University of Texas Rio Grande Valley and Victor Vásquez-Sanchez and Teresa Rosales-Tham of Arqueobios in Peru outline their method of starch grain analysis from ceramic and stone artifacts to investigate the use of potatoes in the Moche diet.

Their archaeological investigation focused on the site of Wasi Huachuma, located in the lower Jequetepeque valley of Peru, dating to 600-850 AD or the later years of the Moche culture. This site featured a platform mound, associated out buildings, burials, and a large residential area. The Moche civilization is well known for massive ritual structures like the pyramidal Huaca del Sol and Huaca de la Luna, as well as for their extensively varied ceramic tradition that includes depictions of sex acts. Some Moche religious practices even involved ritual human sacrifice.

Given the rich history of impressive material culture, less research has been focused over the last century of archaeological investigation of the Moche into domestic contexts, including what food people were eating. But a recent turn in anthropological archaeology away from elite-only contexts to the remains of common people has greatly enriched the prehistory of cultures around the world.

Photo taken on Nov. 7, 2018 shows the bronze pot containing the liquid unearthed from a Western Han Dynasty (202 BC to AD 8) tomb in Luoyang, central China’s Henan Province. Archaeologists on Tuesday poured liquid out of a bronze pot unearthed from the tomb into a measuring glass, giving off an aroma of rich wine.

ZHENGZHOU, Nov. 6 (Xinhua) — Archaeologists in central China’s Henan Province on Tuesday poured liquid out of a bronze pot unearthed from a Western Han Dynasty (202 BC to AD 8) tomb into a measuring glass, which gave off an aroma of rich wine.

“There are 3.5 liters of the liquid in the color of transparent yellow. It smells like wine,” said Shi Jiazhen, head of the Institute of Cultural Relics and Archaeology in the city of Luoyang.

He said the discovered content needs to undergo further lab research so the team can accurately ascertain the ingredients of the liquid.

A large number of color-painted clay pots and bronze artifacts were also unearthed from the tomb, which covers 210 square meters. The remains of the tomb occupant have been preserved, said Shi.

He said they will conduct lab research on items found in the main tomb chamber.

Similar-aged rice wine had earlier been found in other tombs dating back to the Western Han period. Liquor made from rice or sorghum grains were a major part of ceremonies and ritual sacrifices in ancient China. It was often contained with elaborate bronze cast vessels.

Shi said the bronze pot containing the liquid is one of the two big bronze items unearthed from the tomb. The other is a lamp in the shape of a wild goose, which was the first of its kind found in the city of Luoyang, capital of 13 dynasties, with a history of 3,000 years.

She’s quick to add that there is no direct evidence of ancient Maya pirates, but given how much valuable cargo was passing through these ports—and the fact that boats were often depicted carrying armed warriors—it’s a pretty good guess. Chances are, piracy started long before Europeans arrived. The presence of pirates of the ancient Caribbean might also explain the tall pyramid that could serve dual functions: for religious ceremonies and as a lookout. Vista Alegre had another quirk. In pre-Columbian times, the settlement was on a peninsula, with three sides facing the water (the bays on either side have since filled in) and an elaborate stone wall, probably topped by a wooden barrier, guarding the south-facing fourth side. But there appears to be no roads or settlements in that direction. Why build a wall if there’s no one on the other side to keep out?

The wall was likely meant to keep out marauders who, worried about being spotted on the water, would land nearby and try to enter the city by land. Many of the sites along the coast have similar walls to Vista Alegre. The ruins of Isla Cerritos, 100 kilometers to the west, had a 305-meter wall that blocked the harbor like a giant arm shielding the city.

Beyond physical defenses, little else is known about coastal battles of the Maya world. Were there trained ocean fighters? Specially designed warships? Naval strategies? In fact, of the thousands of boats that once littered the coasts, all that has survived is a single canoe preserved in peat soil that dissolved almost as soon as it touched the air and a couple of paddles discovered in Belize. Yet, according to the first Spaniards to visit the coast, the Maya used many types of boats with up to 25 paddlers and capable of hauling over three tonnes of material, which is more than some midsize pickups can handle today.

Some canoes may have even had sails. Several Spanish chroniclers describe seeing sails along the coast—there are no images, however, of sails among the codices and murals of the Maya themselves. Many local people still build traditional boats and even host international paddle races, but it’s tough to know what parts of these traditions are old and which are new.

Modern Maya canoe builders have specific rules about construction. “For example, when to cut down the tree, which tree,” says Mariana Favila, an anthropologist at the National Autonomous University of Mexico, who is writing her PhD thesis on the maritime practices of the Maya, partly by spending time with modern indigenous communities.

She points out that there are many traditions around boatbuilding that seem to predate Europeans, such as a ban on women being near a boat while it’s being built. Local tradition holds that women are associated with cold, whereas men are characterized by heat. Thus, for boats—which are also tied to cold—to stay afloat, they must be kept separate from women.

When most people imagine an ancient Maya city, they probably picture Chichén-Itzá with the commanding El Castillo at its center, surrounded by ball courts of varying sizes and wide plazas. But the sites we see today were the ceremonial centers of the cities, not where people lived. Studying a pyramid is like trying to understand the United States by digging up the Lincoln Memorial. It tells you something about values and traditions, but not daily life.

For that, you need to see where the ancient Maya lived and worked. Modern satellite images and laser-guided surveys from planes have revealed that Maya cities were far more sprawling than anyone would have ever guessed. Earlier this year, a large multinational team announced that several cities in northern Guatemala once presumed separate were, in fact, connected by 60,000 previously unseen structures.

Many of these were wooden houses built on low platforms. But, like giant, ravenous beasts, the tropical landscapes of the Yucatan and Petén Basin gobbled up all the wooden structures they touched, along with tools and boats. Except in one place—an ancient lagoon in Payne’s Creek National Park, a nature preserve encompassing savannah, tropical rainforest, and mangroves in southern Belize.

Heather McKillop, an archaeologist at Louisiana State University, first came to Payne’s Creek in 2004 on an odd sort of archaeological scouting expedition. She knew that there had been settlements in the area and that the ocean had risen since then. So rather than shovels and pickaxes, she brought a swimsuit, a couple of buckets for specimens, and a vague notion that the rich lagoon soils were hiding interesting artifacts probably related to salt making. She and a few students waded into the water and quickly found all sorts of ceramic shards from pots used to boil briny seawater to collect salt and the occasional wooden stump—probably either a dead tree or driftwood washed in from storms.

“Wood doesn’t preserve in the rainforest,” McKillop says. “I thought, oh they’re just old tree roots or they’re pieces of wood that have drifted in.” There’s no way they were left over from the Maya, that would be ridiculous. Termites, shipworms, or thousands of other creatures that scour the jungles and shores for detritus quickly devour wood here. But just out of curiosity, she and her students decided to dig up one.

“I said, if it’s a post, it’s going to go straight down and the end is going to be sharpened. If it’s a tree, it’s going to branch out,” she says, assuming at the time they were all dead trees. “I just want to settle this once and for all.”

They took turns holding their breath, ducking a meter underwater, and scraping around the sides of the logs. The soil was a heavy sort of peat, covered in moss that was perfect for clutching while digging with the other hand. Finally, they got to the bottom and freed the wood, pulling it up to the surface.

“The four of us are looking at it, and the end comes out of the water. And it’s sharpened,” she says. It was like reaching into a wastebasket in Rome and pulling out a poem by Julius Caesar. No one had ever found something like this. “Then they all looked at me and say, ‘So what is it?’”

That same trip, they found more than a dozen sites along the creek and the first-ever intact Maya canoe paddle. Since then, McKillop and her team have found more than 4,000 such posts—perfectly preserved in the oxygen-deprived peat—in a five-square-kilometer area, using masks and snorkels while floating facedown on cleverly modified pool loungers.

The sheer number of posts in such a small area suggests that the coastline once bustled with salt works. Salt is crucial to all civilizations, not just as food but also as a preservative. Experts always assumed the Maya collected it along the shoreline and passed it inland, but now they had evidence of whole communities dedicated to producing salt.

“If you sat on the beach, you would watch two boats go by every single day full of salt. It’s not an occasional thing, this would be a very regular transport schedule,” says Thomas Guderjan, an archaeologist at the University of Texas at Tyler who specializes in Maya agriculture and city planning. “You could not service that population just with an occasional guy who takes a paddle up to get salt. This would be a very structured market.”

No one knows for sure how the ancient Maya economy worked, but trade was likely crucial. Quetzal feathers (found in tropical cloud forests) came downhill, jade (found in the south) went north, shells went inland to the mountains of central Mexico, and obsidian (found in the volcanic spine of the continent) went to the flatlands of the Yucatan. There were no pack animals or wheels for carts, and boats packing a few tonnes of material would have been highly efficient.

But not everyone is so convinced by this picture. Rafael Cobos Palma is an archaeologist at the Autonomous University of the Yucatan with perhaps more experience investigating the coastal Maya than anyone else alive. He doesn’t see some kind of market-based trade but something more like a pipeline completely controlled by elites from Chichén-Itzá.

“Trade is not the correct word to use,” Cobos Palma says. “Nobody else participated. It was a closed system.”

He compares the gold and turquoise coming along the coast to Fabergé eggs created for Russian royalty during the turn of the last century. It’s not really trade if the materials go only in one direction. He admits that there might have been other, less-formal trade systems that siphoned goods to a few other cities, but insists this isn’t because of a market, it’s from leaks in the pipeline.

It’s a controversial idea, considering how long the ports operated and the variety of goods the coastal Maya moved and how different their culture seems from their inland neighbors. But it gets at a fundamental question about the ancient Maya. Did they have an economy the way we think of it—with currency, merchants, and markets? Or was it controlled by the iron fist of the state? Perhaps the answer lies in one of the many unexcavated sites along the coast, like Xel-Ha or Xcalak.

There’s just one problem: many of these sites are underneath multimillion-dollar resorts.

Ironically, the global fascination with the ancient Maya that puts pyramids on magazine covers and in Indiana Jones movies has helped fuel a tourism industry gobbling up wide swaths of the coastline, including many Maya sites. Xel-Ha, an ancient city north of Tulum, is now an amusement park, with playgrounds, rides, and concession stands. Others are in the middle of golf courses, and one, a rare cave shrine, is poking up through a Home Depot parking lot. When Rissolo wanted to see an important shrine at Xcaret, near Playa del Carmen, he had to buy tickets and walk past the souvenir shops and a dolphin tank to get there.

Thankfully, many sites were visited and cataloged by archeologists before the all-inclusive resorts moved in, though most of these studies were just cursory. Still, someday archaeologists may be able to finish what they started.

“The bulldozer might have destroyed one or two platforms here or there but there’s certainly more information. And fortunately, all that information is underneath,” Cobos Palma says.

More destructive might be time itself. Cobos Palma points out that the coast of Tabasco, just west of Vista Alegre, is suspiciously short on ancient sites. The best explanation is that they have been buried under soil or rising seas. One of his research sites, Uaymil, was once on the coast but is now more than a kilometer inland. McKillop’s research area was originally on solid ground until the oceans rose up around it. Others could have been wiped out by a single well-placed hurricane.

But there’s still too much to find to despair about what’s been lost. Some of the most important coastal ports may remain undiscovered.

Back at Vista Alegre, far from the lively coastline of Cancún, Rissolo and Glover finish their survey, and we pile back into our skiff. Unlike the east coast of the Yucatan Peninsula, the northern end is nearly deserted. It’s a beautiful day, with enough wind to kick up some sea spray but it’s still pleasant. The previous week, the area had been buffeted by powerful winds as Subtropical Storm Alberto formed offshore and charged toward Florida. Roads in the area have been flooded for days and Cancún ground to a standstill. And that was just a small storm. Imagine a powerful monster like Hurricane Wilma—which devastated the region in 2005—and it’s easy to see why not everyone has embraced the coast.

“This entire coastline is unpopulated,” says Rissolo, looking west toward the Gulf of Mexico. “From an archaeologist’s perspective, there’s really a great opportunity to study how the ancient Maya organized themselves on the landscape. Imagine trying to do what we’re doing when you’ve got golf courses, all-inclusive resorts, and shopping malls that run all the way from Cancún to Tulum.”

On the way back to the harbor, they decide to take a little detour. Locals say there is perhaps evidence of a settlement on the nearby island of Holbox, an emerging vacation spot for off-the-beaten-path tourists. One archaeologist documented the site in the 1950s, but no other scientist has visited the place. Rumor has it there are a few stone structures and maybe a shrine. Somewhere. Glover pulls out a drone and attempts to launch it.

“That’s a stiff wind, dude,” he says to no one in particular, testing the drone’s rotors. “Not ideal.”

“We don’t even know if it’s in the interior. Is it at the edge of the mangroves? The coastline is just so complex,” Rissolo mutters.

Glover eventually gets the drone airborne and battles the wind for a while, taking video he hopes will later reveal the site. It’s bizarre that there could be an undocumented ancient settlement 100 meters from our boat and we can’t see it. But then again, that’s the story of modern Maya archaeology. In recent years, the biggest discoveries haven’t been pyramids or kings but pedestrian things: ancient farm fields, roads, and salt factories. Seeing how the Maya constructed their civilization, in addition to their sacred buildings, has broadened our view of how their world looked. It was a world of mysterious ceremonies and unusual head shapes, but also one of people who were adept at getting what they wanted quickly and efficiently.

Eventually the researchers give up—Glover is wary of running out of battery power and crashing the drone into the water. They agree to come back, perhaps with kayaks, and inspect the mangroves more carefully.

They fire up the engine and motor toward the mainland. The clouds are almost gone, and tomorrow promises to be another perfect day in paradise. Boatmen will cart tourists to the island, just as they have for decades, while the fishermen load up their nets to leave at first light—just as they have for thousands of years.

Part 1

For thousands of years, ancient Maya kings ruled a vast inland empire in Mexico and Belize. But just how inland was it, really?

Vista Alegre, a ruin of a town near the northern tip of the Yucatan Peninsula in Mexico, was once a bustling outpost. Dozens of canoes crowded the harbor, loaded down with dyes from the west, jade from the south, and obsidian from mountains hundreds of kilometers away. The sound of trumpeting conch shells periodically sliced the air—an alert from sentries scanning the horizon from platforms attached to stone structures. The call signaled an incoming boat—to trade or, perhaps, to plunder.

Within the town, the smell of fish hung heavy in the air as fishermen hurried about with their catches slung across their backs. They passed a man outside his hut hacking a pile of decorative shells into portable sizes for the next outgoing canoe. In another hut, a woman was using salt from a town to the south to dry freshly caught fish that would then be shipped to cities far away. And all the while, smoke from a signal fire atop a pyramid guided exhausted ocean travelers to safe harbor.

Today, a thousand years later, the town isn’t much to look at. Centuries of accumulated dirt and vegetation cover the pyramids. Trees growing on various structures have succumbed to gravity, tumbling and taking with them massive stone blocks once perfectly fitted together.

Today, the ruins of Vista Alegre, on the northern Yucatan coast, are barely visible but still reveal much about the ancient maritime Maya. Video courtesy of Jeffrey Glover and Dominique Rissolo

Though part of the ancient Maya world, which stretched from here all the way into modern-day El Salvador, Vista Alegre lacks the grandeur of many sites. It doesn’t have the dozens of glistening pyramids that lure millions of tourists to Chichén-Itzá, the enticing carvings of Palenque, or the vibrant murals of Bonampak. In fact, were it not for a single pyramid in the middle of a handful of crumbling structures, you might miss its human past altogether. But this small port town at the bottom of the Gulf of Mexico was once part of a complex network of coastal commerce that dominated the ancient world but has been understudied by academics and ignored by the public. Because, unlike Chichén-Itzá or Palenque or Bonampak in the interior of the country, time has nearly erased coastal ports like Vista Alegre from history.

It’s part of a growing collection of archaeological sites revealing a complex and cosmopolitan network of sea traders with their own culture and traditions, who are at once separated from and deeply tied to their more famous compatriots deep in the Yucatan jungles.

“Our knowledge of markets and the role of markets is changing in the Maya area,” says Jeffrey Glover, an archaeologist at Georgia State University. Glover stands on a cluster of exposed blocks at the top of Vista Alegre’s steep central pyramid with its commanding view of the coastline. Looking out, he seems to see the town as it once was, even describing it in the present tense. “There are a lot of people there that need stuff and that want stuff. And they’re probably getting gold from as far south as Panama and Costa Rica, with turquoise that’s coming from the American Southwest.”

Glover and his colleague Dominique Rissolo have been exploring this small site for more than a decade. When they first came to this undeveloped coastline over two hours northwest from Cancún by car and then boat, they expected a small town dependent on the fortunes of the much larger Chichén-Itzá—a nameless cog in the machinery of a great city only 125 kilometers away. But that’s not what they found. Vista Alegre predates the larger city by hundreds of years. The people here ate differently, had different fashions, and traded an astounding diversity of precious things from around Meso-America.

And there was something else here that the archeologists did not expect. The town’s central 10.6-meter-high pyramid is oddly steeper than others in the region—made possible by an unusual concrete recipe that connects its stones and is usually found hundreds of kilometers to the west. This innovation, presumably gleaned from passing travelers, allowed them to build a pyramid tall enough to let them see for a great distance in all directions but with fewer blocks than typical pyramids.

“It blew me away when I saw it. I hadn’t seen anything like that anywhere in this region,” says Rissolo, a researcher at the University of California, San Diego. “There’s a certain kind of cosmopolitan nature to the site, where people are exposed to different styles and different traditions.”

As we walk the grounds, Rissolo regularly leans down to pick up bits of pottery, some 1,500 years old. It turns out that Vista Alegre was just one of dozens of small settlements that rim the Yucatan Peninsula at about 40-kilometer intervals, the distance a team of paddlers can move a goods-laden boat in a day. None of the coastal communities had the grandeur of the bigger Maya cities, but when put together, they paint a vivid picture of commerce in the region. And, in another surprise, of combat.

The Maya are often called “people of corn” because their identity is forever tied to that crop. Academic and popular stories paint pre-Colombian Maya as a peaceful, inland people who tended crops, feared the sea, and looked to the stars. As with all historical generalizations, however, this picture has faded with new discoveries. Modern scientists have found that the real ancient Maya were just as war-prone as Aztecs or Europeans and perfectly comfortable on the sea.

Looking at the bones from sites like Vista Alegre, scientists now know the ancient coastal Maya ate healthier than their inland compatriots, getting more protein from sea life. Evidence suggests they were more egalitarian too, though less sophisticated in their cultural traditions. Take the common ancient practice of head shaping (whereby boards are tied to an infant’s head to cause it to grow a certain way). Whereas people in Calakmul, near the border of modern-day Guatemala, had a myriad of head shapes fashioned from birth, those on the coast kept it simple—just a slightly elongated head. And rather than elaborate jade- or obsidian-inlaid teeth, coastal people tended to simply sharpen them down a little. But that’s not to say they were boring.

The people came from all over, says Vera Tiesler at the Autonomous University of Yucatan. “There was a big melting pot of people there, traveling down the coast.”

Tiesler is a bioarchaeologist. Rather than digging up pyramids or looking for jade jewelry, she studies human remains. From diseases to wounds to DNA, a set of bones can tell you more about people than a stone structure. And while the Maya coastline may not have a lot of fancy pyramids or ornate paintings, it has a lot of bones littered around—the soil composition and high salt levels lead to wonderful bone preservation.

When a Mayanist finds a set of bones, it often finds its way to Tiesler. And after looking at hundreds of ancient skeletons, she’s come to see the coastal Maya as a sort of subculture. Their seafood diet—revealed through bone analysis—suggests that over generations, families spread long distances along the coast but rarely went inland. It was as if once they found the coast, they didn’t want to leave it.

Coastal Maya also fought differently than their inland compatriots. Contrary to their reputation, the ancient Maya engaged in plenty of warfare. Armies would face off with clubs, hatchet-like weapons, and throwing spears called atlatls. In hand-to-hand combat, injuries were mostly sustained on warriors’ left sides from right-handed assailants. But Tiesler says battle scars of the ancient coastal Maya favor no side. Also, ancient armies were usually all male, but a higher-than-expected number of the violent casualties Tiesler sees were women. Plus, many combatants survived, which would be odd on a battlefield. The likely reason for these discrepancies between Maya armed conflict wounds and these coastal casualties? Piracy.